There is a rapidly growing need for environmentally acceptable systems for generating electric power. Clearly, hydroelectric power is one such system. Further, there are many instances when water from various sources must be disposed of in ways that are not deleterious to the environment. One method of dealing with the disposal of water is to inject it into underground reservoirs or other formations.
There are many existing injection wells in the municipal, agricultural, industrial, petroleum, mining and energy oil fields. In some of these injection wells, water falls a considerable distance to the static water level. In cases where the injected water is falling to a sufficient depth, at a sufficient volume, a turbine with a connection to a generator may be installed to recover this energy.
Injection wells are also common in aquifer storage and recovery systems used by many water districts, where the right geologic conditions exist. They are also common in geothermal production where the water/brine is re-circulated to mine more of the heat in the strata. Further, some mines inject dewatering effluent.